Crimping tool for pipe fittings

ABSTRACT

A crimping tool for pipe fittings has a pair of semi-cylindrical opposing jaws with opposing ends, pivotally attached at one end of each, for closing and opening movement about the pivot axis. When closed, the jaws define a cylinder for engaging a pipe or other cylindrical element to be crimped. The other ends of the jaws have integral extensions that meet when the jaws are closed and are clamped together by a simple crimping force assembly comprising a threaded eyebolt, the eye end being pivotally attached to the end of one jaw extension. The bolt swivels in and out of a slot in the other jaw extension. A nut on the other end of the eyebolt is used to compress the two jaw extensions together. In another embodiment, the jaws have annular grooves on their inner surfaces to accommodate the male ridges of ProPress® pipe fittings.

This invention claims the benefit of the inventor's previously filed provisional application, No. 60/699433.

BACKGROUND OF THE INVENTION

This invention is directed to apparatus for crimping and sealing copper fittings joining copper pipe, more particularly for crimping ProPress® fittings.

The need for leakproof conduit for fluids is extensive and entails the use of variously shaped connectors and pipe fittings for routing the conduit. Copper tubing and fittings were traditionally connected by “sweating ” the joints, or with threaded connectors. Then polyvinyl choride (PVC) conduit became widely used, particularly in residential plumbing applications. Sections of PVC were glued together. Later technology substituted flexible PVC and utilized a crimp ring to compress the tubing ends deformably down against a rigid insert positioned in the internal conduit in the tubes. This use of crimp rings is particularly well known in association with elastomeric hose or tubing, where the material possesses sufficient elasticity to be deformed without breaking.

In many large facilities, such as airports, government buildings, sports stadiums, military bases, casinos, hotels, schools, colleges, hospitals and healthcare facilities, copper tubing is preferred for plumbing and heating applications. Recently, threadless, solderless and “sweatless” couplings for copper piping have been developed and are being used in industrial applications where copper pipe is specified. Examples include the axially clamping pipe coupler, subject of U.S. Pat. No. 6,056,330 to Compton et al., and the ProPress® System with its “Smart Connect” feature from Ridge Tool Company of Elyria, Ohio and Viega, a German company, first available in May 2000. The latter system joins copper tubing by crimping the fitting around the tube to form a watertight connection in seconds. The system comprises a series of engineered copper and bronze press fittings offered in over 400 configurations and sizes ranging from ½″-4″. Fittings are offered with distinct sealing elements that, together, meet a broad range of piping applications.

A battery-operated crimp tool, the RIDGID® 320-E, developed by Ridge Tool Co. for use with the ProPress System, weighs ten pounds and is touted as being suitable for joining tube in tight spaces. However, its size, which is slightly larger than a battery-powered hand-held electric drill, prevents its use in very small spaces. U.S. Pat. No. 6,269,675 to Burnett is a manually operated tool which utilizes a threaded bolt to apply crimping force. However the arrangement of parts with a handle adjacent the pivoting connection of the jaws and the complicated crimping-force-application assembly make the invention bulky, awkward to use, and complicated and expensive to manufacture. Accordingly there is a need for a crimping tool that can be used for the ProPress System, that will fit in the spaces which are too small for the RIDGID® 3 20-E, and that is more compact and simpler than the Burnett device.

Thus it is an object of this invention to provide a compact crimping tool that can seal ProPress copper tubing joints satisfactorily in tight spaces too small for use of the RIDGID® 3 20-E battery operated tool, that is compact and simple in construction.

SUMMARY OF THE INVENTION

A crimping tool for pipe fittings has a pair of semi-cylindrical opposing jaws with opposing ends, pivotally attached at one end of each, for closing and opening movement about the pivot axis. When closed, the jaws define a cylinder for engaging a pipe or other cylindrical element to be crimped. The other ends of the jaws have integral extensions that meet when the jaws are closed and are clamped together by a simple crimping force assembly comprising a threaded eyebolt, the eye end being pivotally attached to the end of one jaw extension. The bolt swivels in and out of a slot in the other jaw extension. A nut on the other end of the eyebolt is used to compress the two jaw extensions together. In another embodiment, the jaws have annular grooves on their inner surfaces to accommodate the male ridges of ProPress® pipe fittings.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the first embodiment of the improved pipe crimping tool of the present invention;

FIG. 2 is a perspective view of a ProPress T pipe connector joined to pipe sections;

FIG. 3 is a perspective view depicting the present invention crimping one end of a ProPress T connector to a pipe section.

FIG. 4 is a perspective view of the second embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 2, a T-shaped, hollow ProPress® T-shaped pipe fitting 30 of the type made by the Rigid Tool Company is shown with circumferential ribs 32 spaced near each end 31 of the connector 30. Each rib covers a sealing 0-ring of high-performance elastomer, not shown. When crimped with an appropriate tool, the fitting, copper tubing and sealing ring are combined to form a permanent watertight seal. The ProPress® high-performance fittings are more particularly described and depicted at www.propresssystem.com/ and www.ridgid.com/propresssystem/ppfittings.asp.

Referring now to FIGS. 1 and 3, the present invention 10 comprises a first semicircular jaw 12 opposing and pivotably attached to a second semicircular jaw 16 by first pin 20. Jaw extensions 14 and 18 are integral and extend from jaws 12 and 16 at their free unattached ends. Optimally the jaws and jaw extensions are made of rigid, heavy-weight, tempered metal. Jaw extensions 14 and 18 have slots 22 and 24 at their ends. The slots are aligned when the jaws are closed. The eye end of an eyebolt 26 is pivotably attached within slot 22 by second pin 27. Slot 24 accepts the shaft of eyebolt 26 when the jaws are closed, and the shaft is long enough to extend outside slot 24 far enough so that a nut 28 and lock washer 29 can be threaded onto the end of the shaft to press jaw extensions 14 and 18 together, using a wrench of some kind, such as torque wrench or socket wrench

When the jaws are closed, as in FIG. 3, a closed cylindrical ring is formed. The internal surfaces of jaws 12 and 16 have grooves 32 and 34 aligned to form a continuous annular groove when the jaws 12 and 16 are closed as in FIG. 3. These grooves are configured to accept, completely encircle and compress the male ribs 36 of a ProPress ) pipe fitting to seal a joint when nut 28 is tightened on eyebolt 26. Optionally, a guide pin 15 can be provided on jaw handle 18 to mate with guide hole 17 to ensure that no twisting of jaws 12 and 16 occurs wherein grooves 32 and 34 do not align to form a single annular groove FIG. 4 depicts an alternate embodiment 50 of my invention which has no annular groove on the internal surfaces of jaws 52 and 54. This embodiment is directed to a crimping tool for sealing compression sleeves on plastic pipe.

Both embodiments have the advantage of being relatively small in relation to the other crimping tools now available in the market place. Thus they can be used effectively where space is limited where bulkier crimping tools cannot fit or operate. This invention has fewer parts than the Burnett patent, it lacks a handle adjacent the pivot point of the jaw members. The crimping-force-application assembly is very simple and lacks the bushing, the spindle, the pintles and the retention plates of Burnett. Thus it is less complicated and less expensive to manufacture. 

1. In a manually operable crimping tool comprising first and second opposing semi-cylindrical jaw members with first and second ends, or engaging an element to be crimped, said jaw members being pivotally joined at the first end of each said jaw member, for pivotal opening and closing movement about a first axis, and defining a cylindrical space when closed, further comprising a crimping-force-application assembly including (i) means to pivotally attach said assembly to one of said first and second jaw members for pivotal movement about a second axis generally parallel to said first axis; (ii) means to releasably engage another one of said first and second jaw members, said means to releasably engage being movable between a first disengaged position in which said crimping-force-application assembly is not touching said second jaw member, permitting movement of said first and second jaw members onto and off of the element to be crimped and a second engaged position permitting application of a crimping force; (iii) manually operable means to reduce a distance between said means to pivotally attach said assembly and said means to releasably engage, thereby causing said first and second jaw members to interact to crimp the element therebetween, the improvement comprising a straight bar extension from each said first and second jaw member at their second ends, on which extensions are mounted said crimping-force-application assembly elements.
 2. The improvement of claim 1 wherein said extensions have slots at their second ends, which align when said jaw members are in their second engaged position, and said manually operable means to reduce a distance further comprises a threaded eyebolt having an eye end and a second end, the eye end of said eyebolt pivoting on a pin mounted parallel to said first axis within the slot of the first jaw member extension, and a nut rotatable at the second end of the eyebolt, whereby when said eyebolt is pivoted to lie within both slots of the jaw member extensions with its second end outboard of the second jaw member extension, rotation of the nut causes the jaw member extensions to come together. 